I feel your pain...
My very first H/T was a very cheap Kenwood and I pushed it too hard. It took 3.5 months to get it fixed under warranty, due to there not been any parts available. In the end I wrote to the head office in Australia demanding to know what was going on, and insisted they extend the warranty by the same amount of time it took to get fixed.
Long story short, I got it back 3 weeks after and it lasted 7 years.
I now have my second amp, which is an Integra DTR 7.8. I've had no problems with it at all, and it's been over 8 months.
I know all things can and will break down, it just sucks that for the extra money you've laid out for a top end unit, you get no better service.
Hang in there.